KVM: arm64: Add a vcpu flag to control SVE visibility for the guest

Since SVE will be enabled or disabled on a per-vcpu basis, a flag
is needed in order to track which vcpus have it enabled.

This patch adds a suitable flag and a helper for checking it.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: zhang.lei <zhang.lei@jp.fujitsu.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 6d10100ff870d471cdc78ae57e12cd102e36780a..ad4f7f004498ac64be009caee03078ffaf437cbc 100644 (file)
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -328,6 +328,10 @@ struct kvm_vcpu_arch {
 #define KVM_ARM64_FP_HOST              (1 << 2) /* host FP regs loaded */
 #define KVM_ARM64_HOST_SVE_IN_USE      (1 << 3) /* backup for host TIF_SVE */
 #define KVM_ARM64_HOST_SVE_ENABLED     (1 << 4) /* SVE enabled for EL0 */
+#define KVM_ARM64_GUEST_HAS_SVE                (1 << 5) /* SVE exposed to guest */
+
+#define vcpu_has_sve(vcpu) (system_supports_sve() && \
+                           ((vcpu)->arch.flags & KVM_ARM64_GUEST_HAS_SVE))
 
 #define vcpu_gp_regs(v)                (&(v)->arch.ctxt.gp_regs)